In a message dated 11.11.99 11:17:12 Pacific Standard Time, K7GCO writes:
<< To: w0hh@grapevine.net
Your 160 m antenna load is creating high voltages in the tuner that is
causing the arcing. Change the length of the antenna both ways (at the end
or in the shack) in steps even if non resonant and this will change the load
back at the tuner and the resulting voltages. Or put a big multiple loop at
the end of the 160 m antenna and re-resonate it to 160 m and it also may
increase the bandwidth. It also may end up being short enough to fit the
lot. I've seen a teeter totter affect both ways of Z's back at the feedpoint
and is a neat trick.
The arcing problem in the Johnson MB I had on 40M with a balanced load
was solved by reversing the connections to the balanced differential Xc.
This required less inductance in the tank circuit and lowered the voltage
across the Xc plates. Send me the tuner circuit, antenna layout and I'll see
if I can change the tuner configuration somehow or suggest an antenna change.
I reversed the input and output connections on a tuner one time and solved a
problem.
Try an L network only for 160 m. There are 4 configurations. I've
never had one arc. I've had some strange things happen with tuners over some
60 years that were solved with a very simple change.
K7GCO >>
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